Pesticidal compositions and methods of killing pests using N-polyhalo-alkanesulfenyl carbamoyloximino di-sulfur containing heterocyclic compounds

ABSTRACT

Certain N-polyhaloalkanesulfenyl carbamoyloximino di-sulfur containing heterocyclic compositions have exceptional pesticidal properties and low mammalian toxicity.

This invention relates to methods and compositions for combatinginsects. In another aspect, this invention relates to certainN-polyhaloalkanesulfenyl substituted carbamoyloximino heterocycliccompositions which are novel per se.

The compounds which are employed as the active ingredients in thepesticidal compositions of this invention are the heterocyclic compoundscorresponding to the following general formula: ##STR1## wherein: R¹ islower alkyl having from 1 to 4 carbon atoms, phenyl or phenylsubstituted with one or more halogen, acylamido, methylthio, methoxy, oralkyl substituents having from 1 to 4 carbon atoms or a methylenedioxygroup; R² is trihalomethanesulfenyl; R³ and R⁴ are the same or differentand are hydrogen, lower alkyl having from 1 to 6 carbon atoms, loweralkenyl having from 2 to 6 carbon atoms, halogen substituted alkylhaving from 1 to 6 carbon atoms, alkoxyalkyl having a total of from 2 to6 carbon atoms, alkylthioalkyl, alkylsulfinylalkyl oralkylsulfonylalkyl, having a total of from 2 to 6 carbon atoms, phenylor phenyl substituted with one or more halogen, methoxy or lower alkylsubstituents having from 1 to 4 carbon atoms; A is methylene, ethylene,propylene, ethenylene, propenylene or methylene, ethylene, propylene,ethenylene or propenylene substituted with one or more alkyl groupshaving from 1 to 3 carbon atoms; and x is 0, 1 or 2.

The compositions of this invention can be prepared conveniently inaccordance with the following general reaction scheme: ##STR2## where A,R₁, R₂, R₃ and R₄ are as defined above.

The oxime precursors used in the synthesis described above, can beprepared in the manner described in copending U.S. patent applicationSer. No. 254,271, filed May 17, 1972. The appropriate N-trihalomethanesulfenylcarbamoyl fluoride composition used in this synthesis can beprepared conveniently by the method described in U.S. Pat. No.3,639,471.

The following compositions are illustrative of the new compositions ofthis invention:

4-[(N-methyl-N-trichloromethanesulfenyl)carbamoyloximino]-1,3-dithiolane

2,2-dimethyl-4-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,3-dithiolane

2-Methyl-4-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,3-dithiolane

5-Methyl-4-[(N-methyl-N-trichloromethanesulfenyl)carbamoyloximino]-1,3-dithiolane

5,5-Dimethyl-4-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,3-dithiolane

2-[(N-methyl-N-trichloromethanesulfenyl) carbamoyloximino]-1,4-dithiane

3,3-Dimethyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane

3-Propyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane

3-Isopropyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane

3-Allyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane

3-(2-Methoxyethyl)-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane

2-[(N-ethyl-N-trichloromethanesulfenyl) carbamoyloximino]-1,4-dithiane

2-[(N-methyl-N-trifluoromethanesulfenyl) carbamoyloximino]-1,4-dithiane

3,3,5-Trimethyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane

3,3-Dimethyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithi-5-ene

2-[(N-methyl-N-trichloromethanesulfenyl)carbamoyloximino]-1,4-dithi-5-ene

3,3-Dimethyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiacycloheptane

4-[N-(4-acetamidophenyl)-N-(trifluoromethanesulfenyl)carbamoyloximino]-5-methyl-1,3-dithiolane

2-[N-(4 methylthiophenyl)-N-(trichloromethanesulfenyl)carbamoyloximino]-1,4-dithiane

2-[N-methyl-N-(chlorodifluoromethanesulfenyl)carbamoyloximino]-1,4-dithiane

2-[(N-methyl-N-trichloromethanesulfenyl)carbamoyloximino]-1,4-dithiacyclohept-6-ene

4-[(N-methyl-N-trifluoromethanesulfenyl)carbamoyloximino]-1,3-dithiolane

2-[(N-phenyl-N-trichloromethanesulfenyl) carbamoyloximino]-1,4-dithiane

2-[(N-butyl-N-trichloromethanesulfenyl) carbamoyloximino]-1,4-dithiane

2-[(N-methyl-N-fluorodichloromethanesulfenyl)carbamoyloximino]-1,4-dithiane

3-(3,4-Methylenedioxyphenyl)-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane

3-(4-Chlorophenyl)-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino-1,4-dithiane

3-(2-Chloroethyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane

2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane-4-oxide

2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane-4,4-dioxide

The following examples are illustrative of the procedures used forpreparing the compounds of this invention.

EXAMPLE I PREPARATION OF2-[(N-METHYL-N-TRICHLOROMETHANESULFENYL)-CARBAMOYLOXIMINO]-1,4-DITHIANE

To a solution of 1.35 g of 2-oximino-1,4-dithiane and 2.05 g ofN-methyl-N-trichloromethanesulfenylcarbamylfluoride in 75 ml dioxane,cooled to 20° C, was added 1.01 g triethylamine dropwise over a periodof 2 minutes. The exotherm caused the temperature to rise to 31° C. Thereaction mixture was stirred for additional 30 minutes at ambienttemperature and then quenched with 300 ml of water. The precipitateformed was filtered, collected and recrystallized from acetonitrile. Wt.1.7 g -- m. p. 151°-152° C.

Analysis: Calc'd for C₇ H₉ NO₂ S₃ Cl₃ : C, 23.6; H, 2.5; N, 7.9; Found:C, 23.8; H, 2.5; N, 8.0.

EXAMPLE II PREPARATION OF4-[(N-METHYL-N-TRICHLOROMETHANESULFENYL)-CARBAMOYLOXIMINO]-1,3-DITHIOLANE

To a solution of 2.3 g of 4-oximino-1,3-dithiolane and 3.86 g ofN-methyl-N-trichloromethanesulfenylcarbamylfluoride in 75 ml of dioxane,was added dropwise 1.97 g triethylamine. The ensuing exothermic reactionraised the temperature to 30° C. After stirring at ambient temperaturefor 30 minutes, the mixture was quenched in water. The precipitateformed was collected by filtration. The solid was dissolved inethylacetate, dried with magnesium sulfate and concentrated under reducedpressure. The residual solid was recrystallized fromisopropylethermethylene chloride. Wt. 3.8 g -- m. p. 102°-103° C.

Analysis: Calc'd for C₆ H₇ N₂ O₂ S₃ Cl₃ : C, 21.09; H, 2.06; N, 8.20;Found: C, 21.10; H, 2.14; N, 8.06.

EXAMPLE III PREPARATION OF 2-[(N-METHYL-N-TRICHLOROMETHANESULFENYL)CARBAMOYLOXIMINO]-1,4-DITHIANE-4-OXIDE

To a solution of 5.0 g., 2-[(N-methyl-N-trichloromethanesulfenyl)carbamoyloximino]-1,4-dithiane in 300 ml ethyl acetate - methylenechloride (1:1) was added 4.69 g. of 22.8 percent peracetic acid in ethylacetate. After stirring at ambient temperature for 2 hours the reactionmixture was concentrated under reduced pressure to a residual oil.Crystallized from methanol-ethyl acetate. Wt. 4.0 g., m.p. 144°-145°.

Analysis Calc'd for C₇ H₉ N₂ O₂ S₃ Cl₃ : C, 22.62, H. 2.44, N, 7.54;Found: C, 23.11, H, 2.42, N, 7.64.

EXAMPLE IV PREPARATION OF2-[(N-METHYL-N-TRIFLUOROMETHANESULFENYL)-CARBAMOYLOXIMINO]-1,4-DITHIANE

To a solution of 2.0 g., 2-oximino-1,4-dithiane in 100 ml dioxane wasadded4.85 g., 50 percent solution of N-methyl-N-trifluoromethanecarbamylfluoride in toluene and then 1.61 g triethylamine was added dropwisewith cooling and stirring. After stirring for 2 hours, it was quenchedwith 300ml water. The reaction product was isolated in ethyl acetate,dried over magnesium sulfate and concentrated. Crystallized fromisopropyl ether-acetone. Wt. 3.5 g., m.p. 120°-21°.

Bean Aphid Foliage Spray Test

Adults and nymphal stages of the bean aphid (Aphis fabae Scop.) rearedon potted dwarf nasturtium plants at 65°-70° F. and 50-70 percentrelative humidity, constituted the test insects. For testing purposes,the number of aphids per pot was standardized to 100-150 by trimmingplants containing excess aphids.

The test compounds were formulated by diluting the stock suspension withwater to give a suspension containing 500 parts of test compound permillion parts of final formulation.

The potted plants (one pot per compound tested) infested with 100-150aphids, were placed on a revolving turntable and sprayed with 100-110milliliters of test compound formulation by use of a DeVilbiss spray gunset at 40 psig. air pressure. This application, which lasted 25 seconds,was sufficient to wet the plants to run-off. As a control, 100-110milliliters of a water-acetone-emulsifier solution containing no testcompound were also sprayed on infested plants. After spraying, the potswere placed on their sides on a sheet of white standard mimeograph paperwhich had been previously ruled to facilitate counting. Temperature andhumidity in the test room during the 24 hour holding period were 65°-70°F. and 50-70 percent, respectively. Aphids which fell onto the paper andwere unable to remain standing after being uprighted were considereddead. Aphids remaining on the plants were observed closely for movementand those which were unable to move the length of the body uponstimulation by prodding were considered dead. Percent mortality wasrecorded for various concentration levels.

Southern Armyworm Leaf Spray Test

Larvae of the southern armyworm (Prodenia eridania, (Cram.)), reared onTendergreen bean plants at a temperature of 80°±5° F. anda relativehumidity of 50±5 percent, constituted the test insects.

The test compounds were formulated by diluting the stock suspension withwater to give a suspension containing 500 parts of test compound permillion parts of final formulation. Potted Tendergreen bean plants ofstandard height and age were placed on a revolving turntable and sprayedwith 100-110 milliliters of test compound formulation by use of aDeVilbiss spray gun set at 10 psig air pressure. This application, whichlasted 25 seconds, was sufficient to wet plants to run-off. As acontrol, 100-110 milliliters of a water-acetone-emulsifier solutioncontaining no test compound were also sprayed on infested plants. Whendry, the paired leaves were separated and each one was placed in a 9centimeter Petri dishlined with moistened filter paper. Five randomlyselected larvae were introduced into each dish and the dishes wereclosed. The closed dishes were labeled and held at 80°-85° F. for threedays. Althoughthe larvae could easily consume the whole leaf withintwenty-four hours, nomore food was added. Larvae which were unable tomove the length of the body, even upon stimulation by prodding, wereconsidered dead. Percent mortality was recorded for variousconcentration levels.

Mexican Bean Beetle Leaf Spray Test

Fourth instar larvae of the Mexican bean beetle (Epilachna varivestis,Muls.), reared on Tendergreen bean plants at a temperature of 80°±5° F.and 50±5 percent relative humidity, were thetest insects.

The test compounds were formulated by diluting the stock suspension withwater to give a suspension containing 500 parts of test compound permillion parts of final formulation. Potted Tendergreen bean plants ofstandard height and age were placed on a revolving turntable and sprayedwith 100-110 milliliters of test compound formulation by use of aDeVilbiss spray gun set at 10 psig air pressure. This application, whichlasted 25 seconds, was sufficient to wet plants to run-off. As acontrol, 100-110 milliliters of a water-acetone-emulsifier solutioncontaining no test compound were also sprayed on infested plants. Whendry, the paired leaves were separated and each was placed in a 9centimeter Petri dish lined with moistened filter paper. Five randomlyselected larvae were introduced into each dish, and the dishes wereclosed. The closed dishes were labeled and held at a temperature of80°±5° F. for three days. Although the larvae could easily consume theleaf within 24 to48 hours, no more food was added. Larvae which wereunable to move the length of the body, even upon stimulation, wereconsidered dead.

Fly Bait Test

Four to 6 day old adult house flies (Musca domestica, L.), rearedaccordingto the specifications of the Chemical SpecialitiesManufacturing Association (Blue Book, McNair-Dorland Co., N. Y. 1954;pages 243-244, 261) under controlled conditions of 80°±5° F. and50±5percent relative humidity, were the test insects. The flies wereimmobilized by anesthetizing with carbon dioxide and twenty fiveimmobilized individuals, males and females, were transferred to a cageconsisting of a standard food strainer about five inches in diameterwhichwas inverted over a wrapping-paper-covered surface. The testcompounds wereformulated by diluting the stock suspension with a 10percent (by weight) sugar solution to give a suspension containing 500parts of test compound per million parts of final formulation, byweight. Ten milliliters of the test formulation were added to a soufflecup containing a 1-inch square ofan absorbent cotton pad. This bait cupwas introduced and centered on the blotting paper under the foodstrainer prior to admitting the anesthetizedflies. The caged flies wereallowed to feed on the bait for 24 hours, at a temperature of 80°±5° F.and the relative humidity of 50±5 percent. Flies which showed no sign ofmovement on prodding were considered dead.

Mite Foliage Spray Test

Adults and nymphal stages of the two-spotted mite (Tetranychus urticaeKoch), reared on Tendergreen bean plants at 80±5 percent relativehumidity, were the test organisms. Infested leaves from a stock culturewere placed on the primary leaves of two bean plants six to eight inchesin height, growing in a two-and-a-half inch clay pot. 150-200 Mites, asufficient number for testing, transferred from the excised leaves tothe fresh plants in a period of 24 hours. Following the 24 hour transferperiod, the excised leaves were removed from the infested plants. Thetestcompounds were formulated by diluting the stock suspension withwater to give a suspension containing 500 parts of test compound permillion parts of final formulation. The potted plants (one pot percompound) were placedon a revolving turntable and sprayed with 100-110milliliters of test compound formulation by use of a DeVilbiss spray gunset at 40 psig. air pressure. This application, which lasted 25 seconds,was sufficient to wetthe plants to run-off. As a control, 100-110milliliters of a water solution containing acetone and emulsifier in thesame concentrations as the test compound formulation, but containing notest compound, were also sprayed on infested plants. The sprayed plantswere held at 80±5 percent relative humidity for six days, after which amortality count of motile forms was made. Microscopic examination formotile forms was made on the leaves of the test plants. Any individualwhich was capable of locomotion upon prodding was considered living.

The results of these tests are set forth in Table I below. In thesetests the pesticidal activity of the compounds against aphid, mite,Southern Armyworm, Bean Beetle and House fly was rated as follows:

A = excellent control

B = partial control

C = no control

Dashes indicate no test conducted.

Certain of these compositions were also evaluated to determine theirperoral toxicity to mammals. The animal selected for this experiment wasthe rat. The test results obtained are expressed in terms of the numberofmilligrams of composition per kilogram of weight of the animalrequired to achieve a mortality rate of 50 percent (LD₅₀).

The results of these tests are set forth in Table I below:

                                      TABLE I                                     __________________________________________________________________________                                                        Rat                                                               Army-                                                                             Bean                                                                              House-                                                                            P.O. LD.sub.50            Compound                  m.p. ° C                                                                      Aphid                                                                             Mite                                                                             worm                                                                              beetle                                                                            fly mg/kg                     __________________________________________________________________________         ##STR3##             151-152°                                                                       A A                                                                               A A                                                                              A A                                                                               A A                                                                               A A                                                                               149  15                  II                                                                                 ##STR4##             120-121°                                                                      A   A  A   A   A                             III                                                                                ##STR5##             102-103°                                                                       A A                                                                               A A                                                                              A A                                                                               A A                                                                               A A                                                                                75   13                 IV                                                                                 ##STR6##             120-121.5°                                                                     A A                                                                               A A                                                                              C  B                                                                              A A                                                                               A A                                                                               -- --                    V                                                                                  ##STR7##             132-134°                                                                       A A                                                                               A A                                                                              A A                                                                               A A                                                                               B A                                                                               7.07 0.3                 VI                                                                                 ##STR8##             132-135°                                                                       A A                                                                               A A                                                                              A A                                                                               A A                                                                               A A                                                                               -- --                    VII                                                                                ##STR9##             80-82°                                                                         B A                                                                               C C                                                                              C C                                                                               A A                                                                               A A                                                                               -- --                    VIII                                                                               ##STR10##            144-145°                                                                       A C                                                                               A A                                                                              A A                                                                               A A                                                                               28.3 12.3                    IX                                                                                 ##STR11##            120-121°                                                                       A A                                                                               A A                                                                              A A                                                                               A A                                                                               A A                                                                               -- --                    __________________________________________________________________________

In the above Table, A indicates excellent control, B indicates partialcontrol and C indicates no control. For comparison purposes, there isprovided immediately below the data presented for thetrihalomethanesulfenyl derivative the activity measurements achievedfrom the corresponding methylcarbamoyl derivative adjacent to thechemical designation --NHCH₃. It will be observed from the pesticidaldata given that the activity of the trihalomethanesulfenyl compounds isessentially equivalent to that of the corresponding methyl carbamoylderivatives. However, the mammalian toxicity of thetrihalomethanesulfenylcompositions is dramatically reduced in comparisonto the toxicity of the methylcarbamoyl compositions.

To more clearly illustrate the advantages in thetrichloromethanesulfenyl derivatives over their correspondingmethylcarbamoyl composition, there isset forth in Table II below, acomparison of insect toxicity values obtained following the proceduresdescribed above, expressed in terms of parts per million of compositionrequired to achieve an insect mortality of 50 percent (LD₅₀).

                                      TABLE II                                    __________________________________________________________________________                   Insect Toxicity, LD.sub.50 , ppm                               __________________________________________________________________________                                 Mexican                                                                   Army-                                                                             Bean House                                                                             Rat                                     Compound       Aphid                                                                             Mite  worm                                                                              Beetle                                                                             fly P.O. LD.sub.50                          __________________________________________________________________________    A.                                                                               ##STR12##    5  6 (12)*                                                                             53  52   1    15                                     B.                                                                               ##STR13##   13  7 (3)*                                                                              52  10   2   149                                     __________________________________________________________________________    *() systemic activity                                                     

It is considered significant to observe that the insect toxicity of thetrichloromethanesulfenyl derivative is essentially equivalent to that ofthe methylcarbamoyl composition in all cases except the bean-beetlewhere a five-fold improvement was observed. It is extremely important tonote that the mammalian toxicity of the trichloromethane sulfenylcomposition is only 1/10th that of the methylcarbamoyl compound. Thetrichloromethanesulfenyl composition also had a higher degree ofsystemic activity.

The LD₅₀ values shown in the above Table II were determined bytestingthe compositions over an appropriate concentration range obtainedby serialdilution of the stock suspension with water. The percent killwas plotted on log-probit graph paper versus parts per millionconcentration, and the LD₅₀ read from an eye-fitted line drawn throughthe resultant points.

Systemic treatments were made by drenching 20 milliliters of the testcompound formulation into the soil around the roots of bean plantsgrowingin 21/2 inch clay pots. These pots were held in 4 ounce wax papercontainers to prevent cross-contamination and loss by leaching. Theplantswere 4 inches high at the time of treatment and had been infestedwith mites 24 hours previously. Subsequent steps for testing of thesystemic miticidal activity were the same as those described above forthe spray method of application.

What is claimed is:
 1. An insecticide and miticide compositioncomprising an extender and as an active toxicant an insecticidally ormiticidally effective amount of a compound of the formula: ##EQU1##wherein: R¹ is lower alkyl having from 1 to 4 carbon atoms, phenyl, orphenyl substituted with one or more halogen, acylamido, methylthio,methoxy, or alkyl substituents having from 1 to 4 carbon atoms or amethylenedioxy group attached to adjacent carbon atoms of said phenyl;R²is trihalomethanesulfenyl; R³ and R⁴ may be the same or different andare hydrogen, lower alkyl having from 1 to 6 carbon atoms, lower alkenylhaving from 2 to 6 carbon atoms, halogen substituted alkyl having from 1to 6 carbon atoms, alkoxyalkyl, alkylthioalkyl, alkylsulfinylalkyl, oralkylsulfonylalkyl having a total of from 2 to 6 carbon atoms, phenyl,lower alkylphenyl, halogen substituted phenyl, or lower alkoxyphenyl; Ais methylene, ethylene, propylene, ethenylene, propenylene or methylene,ethylene, propylene, ethenylene or propenylene substituted with one ormore alkyl groups having from 1 to 3 carbon atoms; and x is 0, 1 or 2.2. The composition of claim 1 wherein A is methylene.
 3. The compositionof claim 1 wherein A is ethylene.
 4. The composition of claim 1 whereinR² is trifluoromethanesulfenyl and R¹ is methyl.
 5. The composition ofclaim 1 wherein R² is trichloromethanesulfenyl and R¹ is methyl.
 6. Aninsecticide and miticide composition comprising an extender and as anactive toxicant an insecticidally or miticidally effective amount of a5,5-dimethyl-4-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,3-dithiolane.7. An insecticide and miticide composition comprising an extender and asan active toxicant an insecticidally or miticidally effective amount ofa2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane.8. An insecticide and miticide composition comprising an extender and asan active toxicant an insecticidally or miticidally effective amount ofa3-methyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane.9. An insecticide and miticide composition comprising an extender and asan active toxicant an insecticidally or miticidally effective amount ofa 3,3-dimethyl-2-[(N-methyl-N-trichloromethanesulfenyl)carbamoyloximino]-1,4-dithiane.
 10. An insecticide and miticidecomposition comprising an extender and as an active toxicant aninsecticidally or miticidally effective amount of a4-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,3-dithiolane.11. A method of controlling insects and mites which comprises subjectingthem to a lethal amount of a compound of the formula: ##STR14## wherein:R¹ is lower alkyl having from 1 to 4 carbon atoms, phenyl, or phenylsubstituted with one or more halogen, acyl amido, methylthio, methoxy,or alkyl substituents having from 1 to 4 carbon atoms or amethylenedioxy group attached to adjacent carbon atoms of said phenyl;R²is trihalomethanesulfenyl; R³ and R⁴ may be the same or different andare hydrogen, lower alkyl having from 1 to 6 carbon atoms, lower alkenylhaving from 2 to 6 carbon atoms, halogen substituted alkyl having from 1to 6 carbon atoms, alkoxyalkyl, alkylthioalkyl, alkylsulfinylalkyl, oralkylsulfonylalkyl having a total of from 2 to 6 carbon atoms, phenyl,lower alkylphenyl, halogen substituted phenyl, or lower alkoxyphenyl; Ais methylene, ethylene, propylene, ethenylene, propenylene or methylene,ethylene, propylene, ethenylene or propenylene substituted with one ormore alkyl groups having from 1 to 3 carbon atoms; and x is 0, 1 or 2.12. The method of claim 11 wherein A is methylene.
 13. The method ofclaim 1 wherein A is ethylene.
 14. The method of claim 11 wherein R² istrifluoromethanesulfenyl and R¹ is methyl.
 15. The method of claim 11wherein R² is trichloromethanesulfenyl and R¹ is methyl.
 16. The methodof claim 11 wherein said compound is5,5-dimethyl-4-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,3-dithiolane.17. The method of claim 11 wherein said compound is2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane.18. The method of claim 11 wherein said compound is3-methyl-2-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,4-dithiane.19. The method of claim 11 wherein said compound is3,3-dimethyl-2-[(N-methyl-N-trichloromethanesulfenyl)carbamoyloximino]-1,4-dithiane.
 20. The method of claim 11 wherein saidcompound is4-[(N-methyl-N-trichloromethanesulfenyl)-carbamoyloximino]-1,3-dithiolane.